//*** Rendering form for fractionExtendAndReduce ***
oa.rf.fractionExtendAndReduce = new RenderingForm(
    "fractionExtendAndReduce",
    "Choose equivalent fractions and drag and drop them to the boat.",
    RenderingModeEL.individually,
    "Choose equivalent fractions and drag and drop them to the boat."
);
/**
 * Decides, if a given arithmetic problem type is applicable to a fractionExtendAndReduce rendering form.
 * 
 * @author Linda Eckardt
 * @param {ArithmeticProblemType} ap Type of an arithmetic problem.
 * @return {Boolean} True if given type is applicable, else false.
 */
oa.rf.fractionExtendAndReduce.isApplicableTo = function (apt) {
  return (
    apt instanceof ArithmeticProblemType &&  
    apt.numberType === NumberTypeEL.Fraction  && 
    apt.specialProblemCategory === SpecialProblemCategoryEL.EquivalentFractions
  );  
};